I need help with these two questions

Julius sold five times as many computers as sam sold last year. in total, they sold 78 computers. how many computers did julius sell?

Aline passes through (1,-5) and(-3,7) write an equation for the line in point slope form rewrite the equation in slope intercept form

Astudent must have an average on five test that is greater than it equal to 80% but less than 90% to receive a final grade of b. devon's greades on the first four test were 78% 62% 91% and 80% what range if grades on the fifth test would give him a b in the course? ( assuming the highest grade is 100%)